Abstract

We present a fabricated metal-semiconductor-metal (MSM) photodetector exhibiting an enhanced photocurrent by integrating a nanoscale metallic grating into its contacts. This serves to increase the incident photon flux about the aperture of the device by guiding incident photons as surface plasmon polaritons. High speed time response data shows that the device responsivity may be increased without sacrificing speed. We demonstrate both a photocurrent enhancement and responsivity increase of about 90% at the design wavelength in comparison to otherwise identical MSM photodetectors without integrated nanoscale gratings. The device retains the MSM advantages of simplicity, planarity, and monolithic integrability.

Received 24 November 2008Accepted 31 January 2009Published online 23 February 2009

Acknowledgments:

For financial support, the National Science Foundation, Electronic and Photonic Devices Technology Grant No. ECCS 0702716 is acknowledged, with additional support from the Materials Sciences Division of the U.S. Army Research Office under Award Nos. W911NF-06-1-0127 and W911NF-08-1-0067.